1. Field of the Invention
The present invention relates to bakers' dough processing equipment. More specifically, the invention relates to a rounder bar with an improved shaping surface for converting pieces of dough divided from irregular hunks of dough into rounded spherical dough pieces as the dough pieces are conveyed on a belt of a surface conveyor along a dough processing path.
2. Description of the Related Art
In a typical commercial bread making process, baker's dough, which is primarily made of flour and water, is blended in a large mixer. A particularly high water content usually is desirable in the dough composition formed in the mixer because a high water content tends to make a softer baked product. Gluten, which is a component of flour, absorbs and retains the water which is added to the mixer so that a dough of a sticky paste-like consistency is made. After mixing, the sticky dough is then transferred, in a preferred method, to a stuffing pump which forms the dough into a stream or moving bar of dough that passes through a conduit to dough processing equipment. The processing equipment can include, among others, a dough distribution manifold which distributes the stream of dough into multiple streams of dough, a dough divider which continually divides the dough streams into pieces of dough of equal volume and deposits the dough pieces in multiple columns of dough pieces onto a moving belt of a surface conveyor for further processing along a processing path.
In order to produce high quality bread and roll-type bakery products, baker's dough processing typically includes the steps of rounding the volumetrically sized dough mass into a spherical shape and developing the outer skin of the sphere into a continuous rubber-like sheet. These steps, when accomplished correctly, result in a dough piece: (1) that is dryer on its outer surface, which improves downstream machinability; (2) that retains gas, which is a byproduct of the fermentation process, resulting in improved volume and grain structure; (3) that provides a more uniform outer crust in the baked-out product, and; (4) that provides a more uniform result when the dough piece is sheeted-out, e.g. flattened into a disk-like shape, or moulded, e.g. rolled up like a cigar.
Typically, divided dough pieces are delivered under the influence of gravity to the upper surface of an endless belt-type conveyor. Stationary rounder bars are positioned along the length of the belt and are angularly offset from the direction of travel of the belt. Rounder bars used for this purpose are disclosed, for example, in U.S. Pat. Nos. 4,008,025, 4,306,850, 5,264,232, 5,270,070, 5,356,652, and 5,714,178. Each of the rounder bars has a concave shaping surface which faces an oncoming column of dough pieces and which forms an elongated pocket with the belt for contacting and shaping the surfaces of the dough pieces as the dough pieces are moved along the shaping surface of the rounder bar by the conveyor belt.
When a dough piece is dropped on the belt of a surface conveyor and contacts the shaping surface of a rounder bar, the dough piece decelerates from the speed of the belt, i.e. to approximately 1/2 of the speed of the belt, and rotates on both the shaping surface of the rounder bar and the upper surface of the conveyor belt. This behavior is caused by frictional engagement of the outer surface of the dough piece with the shaping surface of the rounder bar and causes the dough piece to take on an approximately round shape, flattened only where it contacts the belt, as the dough piece is forced to rotate about various axes while passing down the length of the rounder bar. However, depending on certain characteristics, such as the shape of the shaping surface of the rounder bar, the coefficient of friction of the rounder bar, the stickiness of the dough pieces, etc, the dough pieces can sometimes stick to the rounder bar and lift away from the belt or, otherwise, fail to rotate down the length of the rounder bar as a homogeneous mass, thereby failing to obtain the desired rounded shape and causing individual dough pieces to slide and stick together, i.e. double-up. Therefore, it is known in the prior art to apply oil, i.e. vegetable oil, onto the shaping surface of the rounder bars in order to promote proper shaping of the dough pieces by reducing the tendency of the dough pieces to stick to the shaping surface and the belt. However, adding contaminates, such as vegetable oil, along a dough processing path produces undesirable results, such as allowing the dough piece to slide down the rounder bar, thereby changing the time that it takes for a dough piece to rotate down the length of the rounder bar and causing blemishes on the surface of the baked-out product.
In order to promote the rotation of dough pieces along the shaping surface of a rounder bar, some prior art rounder bars are formed with a roughened textured shaping surface. The roughened surface retards the sliding of the dough pieces against the shaping surface and a slick material formed over the roughened surface permits the dough pieces to release from the shaping surface. Some rounder bars also have incorporated a series of grooves cut into the shaping surface with the raised ridges formed between adjacent grooves acting as a roughened surface for retarding the sliding of the dough pieces.
Additionally, some prior art rounder bars incorporate a compression section of the shaping surface of the bar which has a progressively reduced cross-sectional area between the downwardly facing portion of the shaping surface and the upper surface of the belt of the conveyor through which the dough pieces advance. This constricted area progressively downwardly compresses or squashes the dough piece as the dough piece rolls against the rounder bar and the conveyor belt in order to promote rotation of the dough piece as a homogeneous mass of dough. Heretofore, the narrowest portion of a prior art compression section typically has been arranged as close as 12-14 inches from the entrance end of a rounder bar, thereby gradually increasing the downward squashing action on a dough piece as the dough piece travels the initial 12-14 inches along the length of the bar. However, if the downward squashing force created by the compression section of the rounder bar is too great, the axis of rotation of the dough piece is changed abruptly, oftentimes causing a dough piece to stutter along the length of the rounder bar, slip on the belt of the conveyor or, otherwise, advance un-uniformly and becoming misaligned with other dough pieces, and possibly improperly forming the dough pieces into an undesired shape. Therefore, it is known in the prior art to gradually increase the downward force applied by a rounder bar on a dough piece by extending the compression section of the rounder bar along at least the first 12 inches of the length of the rounder bar to decrease the severity of the downward slope of the shaping surface from the entrance of the bar to the compression section. However, the gradual downward slope of the sloping surface of the prior art rounder bars tends to allow slippage of the dough pieces against the shaping surfaces of the rounder bars, resulting in less shaping and developing of the exterior of the dough pieces.
Therefore, it is desirable to provide improved rounder bars which address these and other shortcomings of the prior art.